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Zuberbühler, Klaus

Nom
Zuberbühler, Klaus
Affiliation principale
Fonction
Professeur ordinaire
Email
klaus.zuberbuehler@unine.ch
Identifiants
https://libra.unine.ch/handle/123456789/670
_
0000-0001-8378-088X

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  • Publication
    Accès libre
    Predator-deterring alarm call sequences in Guereza colobus monkeys are meaningful to conspecifics
    (2010)
    Schel, Anne Marijke
    ;
    Candiottia, Agnès
    ;
    Zuberbühler, Klaus 
    Guereza colobus monkeys, Colobus guereza, produce acoustically conspicuous vocalizations, the roars, in response to their main predators, leopards, Panthera pardus, and crowned eagles, Stephanoaetus coronatus. Roaring alarm utterances generally consist of the same basic call types but differ in overall structural composition. Leopards trigger roaring alarms containing many roaring sequences of only a few calls each, while eagles trigger few sequences with many calls each. To investigate whether conspecifics extract meaning from these structural differences, we played back leopard and eagle alarm call sequences and compared the monkeys’ responses in terms of their locomotor, gaze and vocal behaviour with their responses to the corresponding predator vocalizations. Locomotor responses did not differ between playback conditions; movement was always towards the simulated caller with no clear patterns in the vertical plane. Gaze direction, however, was highly predator specific. When hearing leopard-related stimuli, monkeys were significantly more likely to scan the area beneath them than when hearing eagle-related stimuli, which caused more scanning above. Vocal response rates to conspecific alarms were generally low but comparable with rates to the corresponding predators. If monkeys called, however, they produced the matching call sequences. Overall, our results showed that Guerezas discriminated between predator alarm call sequences produced by unfamiliar conspecifics and responded to them in predator-specific ways. Since the sequences were composed of the same basic call types, we concluded that the monkeys attended to the compositional aspects of these utterances.
  • Publication
    Accès libre
    Male blue monkeys alarm call in response to danger experienced by others
    Papworth, Sarah
    ;
    Böse, Anne-Sophie
    ;
    Barker, Jessica
    ;
    Schel, Anne Marijke
    ;
    Zuberbühler, Klaus 
    Male blue monkeys (Cercopithecus mitis stuhlmanni) of Budongo Forest, Uganda, produce two acoustically distinct alarm calls: hacks to crowned eagles (Stephanoaetus coronatus) and pyows to leopards (Panthera pardus) and a range of other disturbances. In playback experiments, males responded to leopard growls exclusively with a series of pyows and to eagle shrieks predominantly with hacks. Responses to playbacks of these alarm call series matched the responses to the corresponding predators, suggesting that the calls conveyed something about the nature of the threat. When responding to a series of hacks, indicating an eagle, males responded predominately with hacks, but produced significantly more calls if their group members were close to the playback stimulus than far away, regardless of their own position. When responding to a series of pyows, indicating a range of disturbances, males responded with pyows, but call rates were independent of the distance of other group members. The results suggest that males took into account the degree of danger experienced by other group members.
  • Publication
    Accès libre
    Responses to leopards are independent of experience in Guereza colobus monkeys
    Schel, Anne Marijke
    ;
    Zuberbühler, Klaus 
    How primates learn to recognise the predatory species from their animate world is a largely unresolved problem. We conducted predator encounter experiments with wild Guereza colobus monkeys of the Sonso area of Budongo Forest, Uganda. The monkeys are hunted by crowned eagles and chimpanzees, but not leopards, which have been locally extinct for decades. Despite their unfamiliarity with this predator, monkeys reliably produced appropriate anti-predator behaviour to leopards, which was indistinguishable from that of a neighbouring population, where leopards are present. In both populations, monkeys produced the same vocal responses and predator-specific alarm calls, although leopard-naïve monkeys were more inclined to approach when hearing a leopard than monkeys that were familiar with this predator. Control experiments showed that the monkeys’ response pattern was not due to the effects of unfamiliarity or conspicuousness of the experimental stimuli. Natural selection appears to have endowed these primates with a cognitive capacity to recognise direct signs of leopard presence as inherently dangerous requiring specific anti-predator responses.
  • Publication
    Accès libre
    Mixed-species associations of Diana and Campbell's monkeys: The costs and benefits of a forest phenomenon
    Wolters, Sonja
    ;
    Zuberbühler, Klaus 
    One of the most striking behavioural patterns of many forest primates concerns their tendency to live in semi-permanent mixed-species groups. Functional investigations have ascertained that individuals obtain some antipredator benefits without paying the costs of intra-species resource competition. Despite these advances, very little is known about the subtle mechanisms that keep mixed species groups together on a daily basis. Our results showed that in the Diana-Campbell's monkey association both species benefited from each other in diverse and idiosyncratic ways. In the presence of Campbell's monkeys the conspicuous Diana monkeys were more likely to descend into the lower forest strata, increased their foraging behaviour, and individuals became less vigilant. The cryptic Campbell's monkeys, in turn, were able to use the higher forest strata and exposed areas more often, spread out over larger areas, were more likely to travel, and engaged in more conspicuous vocal behaviour when associated with Diana monkeys. These data suggested that both species benefited from each other in ways that went beyond passive group-size related antipredator benefits, such as a dilution effect and increased chances of predator detection. Instead, the increased safety of the mixed species group allowed individuals to exploit their ecological niche more broadly, to forage more efficiently, and to engage in more social behaviour, suggesting that the benefits of mixed species groups are much more varied and diverse than currently thought.
  • Publication
    Accès libre
    Alarm Calls
    Zuberbühler, Klaus 
    Alarm calls are a firm constituent of antipredator behavior in many species. They are interesting because they provide an evolutionary conundrum. Why behave conspicuously in the face of a predator? Research is reviewed showing that the main evolutionary forces, such as individual, kin, and sexual selection, have favored the evolution and maintenance of alarm call behavior in various ways. Second, alarm calls are interesting from a cognitive perspective because they provide an entryway into an animal's mind. Research with nonhuman primates has been particularly fruitful in showing how our closest relatives recruit cognitive abilities similar to those involved in speech processing.
  • Publication
    Accès libre
    Anti-predator strategies of free-ranging Campbell's monkeys
    Ouattara, Karim
    ;
    Lemasson, Alban
    ;
    Zuberbühler, Klaus 
    Habitat type, predation pressure and reproductive interests are all thought to determine the anti-predator behaviour of non-primates, but only few systematic studies exist. Here, we experimentally elicited anti-predator behaviour in six different groups of forest-living Campbell’s monkeys, using visual and acoustic models of leopards, crowned eagles, and snakes. Individuals produced a variety of anti-predator behaviours, depending on the type of predator and whether or not it was visible. Adult males generally behaved conspicuously, either by attacking eagles or producing threat behaviours at a distance to leopards. Adult females remained cryptic to eagles, but joined their male in approaching leopards. To snakes, both males and females responded strongly to familiar Gaboon vipers, but far less to unfamiliar black mambas. Finally, if a predator could only be heard, both males and females produced fewer alarm calls and often changed their vertical position in the canopy (upwards for leopards; downwards for eagles), despite all predator vocalisations being presented from the ground. We concluded that Campbell’s monkeys display sex-specific anti- predator behaviours, which are largely driven by the predators’ hunting techniques, mode of predator detection and the forest habitat structure.
  • Publication
    Accès libre
    The alarm call system of two species of black-and-white colobus monkeys (Colobus polykomos and Colobus guereza)
    Schel, Anne Marijke
    ;
    Tranquilli, Sandra
    ;
    Zuberbühler, Klaus 
    Vervet monkey alarm calling has long been the paradigmatic example of how primates use vocalizations in response to predators. In vervets, there is a close and direct relationship between the production of distinct alarm vocalizations and the presence of distinct predator types. Recent fieldwork has however revealed the use of several additional alarm calling systems in primates. Here, the authors describe playback studies on the alarm call system of two colobine species, the King colobus (Colobus polykomos) of Taï Forest, Ivory Coast, and the Guereza colobus (C. guereza) of Budongo Forest, Uganda. Both species produce two basic alarm call types, snorts and acoustically variable roaring phrases, when confronted with leopards or crowned eagles. Neither call type is given exclusively to one predator, but the authors found strong regularities in call sequencing. Leopards typically elicited sequences consisting of a snort followed by few phrases, while eagles typically elicited sequences with no snorts and many phrases. The authors discuss how these call sequences have the potential to encode information at different levels, such as predator type, response-urgency, or the caller’s imminent behavior.
  • Publication
    Accès libre
    Cooperation and competition in two forest monkeys
    Eckardt, Winnie
    ;
    Zuberbühler, Klaus 
    Putty-nosed monkeys, Cercopithecus nictitans stampflii, occur at various sites in West Africa, particularly in the transition zone between rainforest and savannah. The species is sometimes seen in primary rainforest, although at a curiously low density compared with that of other monkey species. We conducted a 24-month field study in the tropical rainforest of Taï National Park, Ivory Coast, and found that putty-nosed monkeys require an ecological niche almost identical to that of the Diana monkeys, Cercopithecus diana diana. Moreover, the niche breadth of putty-nosed monkeys was significantly decreased in the presence of Diana monkeys, suggesting that feeding competition with Diana monkeys kept putty-nosed monkeys from successfully colonizing a rainforest habitat. However, contrary to the interspecies competition hypothesis, groups of both species almost completely overlapped in home ranges and formed near-permanent mixed-species associations, rather than avoiding each other. We hypothesized that Diana monkeys tolerated immigrating putty-nosed monkeys and formed mixed-species groups with them, despite high levels of competition, because of their merit in predation defense. Direct observations and a series of field experiments confirmed that male putty-nosed monkeys play a vital role in defense against crowned eagles, suggesting that putty-nosed monkeys obtain access to feeding trees by offering antipredation benefits to Diana monkeys. We discuss these findings in light of biological market theory.
  • Publication
    Accès libre
    Predation increases acoustic complexity in primate alarm calls
    Stephan, Claudia 
    ;
    Zuberbühler, Klaus 
    According to most accounts, alarm calling in non-human primates is a biologically hardwired behaviour with signallers having little control over the acoustic structure of their calls. In this study, we compared the alarm calling behaviour of two adjacent populations of Diana monkeys at Taï forest (Ivory Coast) and Tiwai Island (Sierra Leone), which differ significantly in predation pressure. At Taï, monkeys regularly interact with two major predators, crowned eagles and leopards, while at Tiwai, monkeys are only hunted by crowned eagles. We monitored the alarm call responses of adult male Diana monkeys to acoustic predator models. We found no site-specific differences in the types of calls given to eagles, leopards and general disturbances, but there were consistent differences in how callers assembled calls into sequences. At Tiwai, males responded to leopards and general disturbances in the same way, while at Taï, males discriminated by giving call sequences that differed in the number of component calls. Responses to eagles were identical at both sites. We concluded that Diana monkeys are predisposed to use their repertoire in context-specific ways, but that ontogenetic experience determines how individual calls are assembled into meaningful sequences.
  • Publication
    Accès libre
    Hunting behaviour in West African forest leopards
    Jenny, David
    ;
    Zuberbühler, Klaus 
    La panthère Panthera pardus est un prédateur majeur de mammifères dans l’écosystème de la forêt pluviale en Afrique Occidentale. La plupart des renseignements sur le comportement de chasse des panthères est tirèe d’études menées dans des habitats ouverts de la savane, tandis que peu est connu sur les panthères forestières. Les données que nous avons rassemblées par radio-émetteurs et les analyses des crottes montrent plusieurs différences entre les panthères forestières et des populations de savane. Les panthères forestières sont des chasseurs diurnes et crépusculaires qui suivent le schéma d'activité de leur proie. Ils déploient des différences saisonnières et développent des préférences de proie fortement individualisées. Nos conclusions défient l'image répandue des panthères comme prédateurs opportunistes nocturnes., The leopard (Panthera pardus) is a major predator of mammals within the rainforest ecosystem of West Africa. Most of the available information on leopard hunting behaviour comes from studies conducted in open savannah habitats, while little is known about forest leopards. Our radio-tracking data and scat analysis show that forest leopards differ in various ways from the savannah populations. Forest leopards are diurnal and crepuscular hunters who follow the activity pattern of their prey species. They exhibit seasonal differences in activity patterns, and they develop highly individualized prey preferences. These findings challenge the widespread notion of leopards as opportunistic nocturnal predators.